1. Field of Art
The disclosure generally relates to clock generation. More specifically, the disclosure relates to generating a low power high accuracy on die reference clock.
2. Description of the Related Art
During operation, many systems with an integrated circuit utilize an external reference clock generated by a crystal and corresponding clock generator. An external clock adds undesirable cost and size to the system. An on chip solution, while reducing footprint, should consume little power and be unlikely to produce an inaccurate clock frequencies due to changes in process, voltage, or temperature. One on chip solution is to utilize an LC circuit as an on chip reference clock. However, this results in high power drain when the LC circuit is powered. Microelectromechanical systems (MEMS) resonators may also be used to integrate a reference clock on chip. However, a MEMS resonator design has drawbacks as well including sensitivity to changes in temperature and a special, non-standard, foundry process which significantly increases manufacturing costs. MEMS resonators also suffer from high power draw similar to LC circuits. Designers of modern systems desire a low cost and low power reference clock that does not impede slim and non-intrusive system design.